Abu Abbas was sent to bring an end to the hijacking of the Achille Lauro

Italy actually held Abu Abbas 18 years ago and let him go.

The Abbas affair led to the worst post-war crisis between Italy and the USA as well as to the resignation of the then Prime Minister, Bettino Craxi.

The Egyptian plane carrying the hijackers of the cruiser, the Achille Lauro, to Tunis after the end of the stand-off was intercepted by US military planes and forced to land at the US military base of Sigonella, Sicily, on the night of 11 to 12 October 1985.

US authorities were keen to arrest the hijackers as well as Mr Abbas, who had been sent by Palestinian leader Yasser Arafat to Egypt as a negotiator to resolve the crisis.

Italy is such a beautiful country that even its jails cannot be frightening

Abu Abbas

But the Italian premier appealed to the principle of territorial sovereignty and refused to extradite the group.

A very tense confrontation arose between Italian and US military at the Sigonella base.

Fulvio Martini, then head of Italy's military secret service, later described those hours as "a real tug-of-war".

Eventually, the plane with the hijackers was escorted to Rome and Abbas, the leader of the Palestine Liberation Front, was allowed to leave for Yugoslavia.

But the move triggered a major political crisis.

Craxi was eventually forced to resign

In an act of protest, the Republican ministers, led by then Defence Minister Giovanni Spadolini, resigned en masse the following day.

Only one week later, the international crisis was patched up at a G7 summit in New York, where Craxi and then US President Ronald Reagan resolved their differences in a face-to-face meeting.

But Craxi himself was eventually forced to step down.

In November, an Italian prosecutor issued an arrest warrant for Mr Abbas.

He was charged with having masterminded the hijacking. and received a life sentence in absentia in May 1987 - a verdict confirmed in 1988 by Italy's supreme court.

"Italy is such a beautiful country that even its jails cannot be frightening," Abbas told daily newspaper La Repubblica in a 1998 interview.

"I'd rather consider that verdict as an invitation to pay you a visit, sooner or later," he added.

BBC Monitoring, based in Caversham in southern England, selects and translates information from radio, television, press, news agencies and the Internet from 150 countries in more than 70 languages.